American Dryer Corp. AD-235D User manual

AD-235D/AD-235ED
Installation Manual
ADC Part No. 113118
For replacement parts, contact the reseller from which the dryer
was purchased or
American Dryer Corporation
88 Currant Road
Fall River MA 02720-4781
Telephone: [phone] / Fax: [phone]
e-mail: [email protected]
110199JEV/tcosta
WARNING: For your safety the
information in this manual must be
followed to minimize the risk of fire or
explosion or to prevent property damage,
personal injury or death.
Do not store or use gasoline or other flammable
vapor and liquids in the vicinity of this or any
other appliance.
WHAT DO YOU DO IF YOU SMELL GAS
*Do not try to light any appliance.
*Do not touch any electrical switch; do not use
any phone in your building.
*Clear the room, building or area of all
occupants.
*Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's
instructions.
*If you cannot reach your gas supplier, call the
fire department.
Installation and service must be performed by a
qualified installer, service agency or the gas
supplier.
AVERTISSEMENT: Assurez-vous de bien
suivre les instructions données dans cette
notice pour réduire au minimum le risque
d’incendie ou d’explosion ou pour éviter tout
dommage matériel, toute blessure ou la mort.
Ne pas entreposer ni utiliser d’essence ni
d’autres vapeurs ou liquides inflammables dans
le voisinage de cet appareil ou de tout autre
appareil.
QUE FAIRE SI VOUS SENTEZ UNE ODEUR
DE GAZ:
*Ne pas tenter d’allumer d’appareil.
*Ne touchez à aucun interrupteur. Ne pas
vous servir des téléphones se trouvant dans
le bâtiment où vous vous trouvez..
*Évacuez la pièce, le bâtiment ou la zone.
*Appelez immédiatement votre fournisseur de
gaz depuis un voisin. Suivez les instructions
du fournisseur.
*Si vous ne pouvez rejoindre le fournisseur
de gaz, appelez le service des incendies.
L’installation et l’entretien doivent être assurés
par un installateur ou un service d’entretien
qualifié ou par le fournisseur de gaz.

Retain This Manual In A Safe Place For Future Reference
American Dryer Corporation products embody advanced concepts in engineering, design, and safety. If this product is
properly maintained, it will provide many years of safe, efficient, and trouble-free operation.
ONLY qualified technicians should service this equipment.
OBSERVEALLSAFETYPRECAUTIONS displayed on the equipment or specified in the installation manual included with
the dryer.
The following “FOR YOUR SAFETY” caution must be posted near the dryer in a prominent location.
“IMPORTANT NOTE TO PURCHASER”
Information mustbe obtained from your local gas supplier on the instructions
to be followed if the user smells gas. These instructions must be posted in a
prominent location near the dryer.
FOR YOUR SAFETY
Do not store or use gasoline or
other flammable vapors or
liquids in the vicinity of this or
any other appliance.
POUR VOTRE SÉCURITÉ
Ne pas entreposer ni utiliser d’essence
ni d’autres vapeurs ou liquides
inflammables dans le voisinage de cet
appareil ou de yout autre appareil.
We have tried to make this manual as complete as possible and hope you will find it useful. ADC reserves the right to make
changes from time to time, without notice or obligation, in prices, specifications, colors, and material, and to change or
discontinue models.
Important
For your convenience, log the following information:
DATE OFPURCHASE ____________________________ MODELNO. __________________________________________
RESELLER’S NAME _______________________________________________________________________________________
Serial Number(s) ________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
Replacement parts can be obtained from your reseller or theADCfactory. When orderingreplacement partsfrom thefactory,
you can FAX your order to ADC at [phone] or telephone your order directly to the ADC Parts Department at
[phone]. Please specify the dryermodelnumber andserialnumberin addition to thedescription andpartnumber,so
that your order is processed accurately and promptly.

IMPORTANT
YOU MUST DISCONNECT and LOCKOUT THE ELECTRIC SUPPLY and THE GAS
SUPPLY BEFORE ANY COVERS or GUARDS ARE REMOVED FROM THE
MACHINE TO ALLOW ACCESS FOR CLEANING, ADJUSTING, INSTALLATION, or
TESTING OF ANY EQUIPMENT per OSHA (Occupational Safety and Health
Administration) STANDARDS.
CHILDREN SHOULD NOTBEALLOWED TO PLAY ON OR NEAR THE DRYER(S).
WARNING
CHILDREN SHOULD BESUPERVISED IF NEAR DRYER(S) IN OPERATION.
DRYER(S) SHOULD NEVER BE LEFT UNATTENDED WHILE IN OPERATION.
CAUTION
FOR YOUR SAFETY
DO NOT DRY MOP HEADS IN THE DRYER.
DO NOT USE DRYER IN THE PRESENCE OF DRY CLEANING FUMES.
WARNING
UNDER NO CIRCUMSTANCES should the door switch or the heat circuit devices
ever be disabled.
“Caution: Label all wires prior to
disconnection when servicing controls. Wiring
errors can cause improper operation.”
«Attention: Lordesopérationsd’entretien
des commandes étiqueter tous fils avant
de les déconnecter. Toute erreur de
câblage peut étre une source de danger et
de panne.»

WARNING
The dryer must never be operated with any of the back guards, outer tops, or service
panels removed. PERSONAL INJURY or FIRE COULD RESULT.
IMPORTANT
PLEASE OBSERVEALLSAFETY PRECAUTIONS displayed on the equipment and/or
specified in the installation manual included with the dryer.
The wiring diagram for the dryer is located in the front electrical control box area.
DRYER MUST NEVER BE OPERATED WITHOUT THE LINT FILTER/SCREEN IN
PLACE, EVEN IF AN EXTERNAL LINT COLLECTION SYSTEM IS USED.
WARNING

Table of Contents
SECTION I
IMPORTANT INFORMATION..........................................................................3
A. RECEIVING and HANDLING ................................................................................................. 3
B. SAFETY PRECAUTIONS ........................................................................................................ 4
SECTION II
SPECIFICATIONS..............................................................................................6
A. Specifications ............................................................................................................................. 6
SECTION III
INSTALLATION PROCEDURES ......................................................................9
A. UNPACKING/SETTING UP .................................................................................................... 9
B. LOCATION OF THE DRYER .................................................................................................. 9
C. DRYER ENCLOSURE REQUIREMENTS ..............................................................................11
D. FRESH AIR SUPPLY ...............................................................................................................11
E. EXHAUST REQUIREMENTS ................................................................................................ 13
F. ELECTRICAL INFORMATION ............................................................................................. 17
G. GAS INFORMATION ............................................................................................................ 21
H. PREPARATION FOR OPERATION....................................................................................... 25
I. PREOPERATIONAL TESTS .................................................................................................. 25
J. SHUT DOWN INSTRUCTIONS ........................................................................................... 27
SECTION IV
OPERATING INSTRUCTIONS .......................................................................28
A. STARTING THE DRYER ........................................................................................................ 28
SECTION V
SERVICE/PARTS INFORMATION .................................................................30
A. SERVICE ................................................................................................................................ 30
B. PARTS ..................................................................................................................................... 30
SECTION VI
WARRANTY INFORMATION .........................................................................31
A. RETURNING WARRANTY CARD(S) ................................................................................... 31
B. WARRANTY .......................................................................................................................... 31
C. RETURNING WARRANTY PART(S) .................................................................................... 31
SECTION VII
ROUTINE MAINTENANCE ............................................................................33
A. CLEANING ............................................................................................................................ 33
B. ADJUSTMENTS ..................................................................................................................... 35
C. LUBRICATION ...................................................................................................................... 35

SECTION VIII
TROUBLESHOOTING.....................................................................................36
SECTION IX
DATA LABEL LOCATION/INFORMATION ..................................................42
A. Data Label .............................................................................................................................. 42
SECTION X
PROCEDURE FOR FUNCTIONAL CHECK OF REPLACEMENT
COMPONENTS ................................................................................................44
SECTION XI
BURNER/TUMBLER HI-LIMIT MANUAL RESET INSTRUCTIONS.........47

P
SECTION I
IMPORTANT INFORMATION
A. RECEIVING and HANDLING
The dryer is shipped in a protective stretch wrap cover with protective cardboard corners and top cover (or
optional box) as a means of preventing damage in transit. Upon delivery, the dryer and/or packaging, and
wooden skid should be visually inspected for shipping damage. If any damage whatsoever is noticed, inspect
further before delivering carrier leaves.
Dryers Damaged in Shipment:
1. ALL dryers should be inspected upon receipt and before they are signed for.
2. If there is suspected damage or actual damage, the trucker’s receipt should be so noted.
3. If the dryer is damaged beyond repair, it should be refused. Those dryers which were not damaged in a
damaged shipment should be accepted, but the number received and the number refused must be noted
on the receipt.
4. If you determine that the dryer was damaged after the trucker has left your location, you should call the
delivering carrier’s freight terminal immediately and file a claim. The freight company considers this
concealed damage. This type of freight claim is very difficult to get paid and becomes extremely difficult
when more than a day or two passes after the freight was delivered. It is your responsibility to file freight
claims. Dryer/parts damaged in transit cannot be claimed under warranty.
5. Freight claims are the responsibility of the consignee, and ALL claims must be filed at the receiving end.
ADC assumes no responsibility for freight claims or damages.
6. If you need assistance in handling the situation, please contact the ADC Traffic Manager at
[phone].
IMPORTANT: The tumbler section of the dryer must be transported and handled in an upright
position at ALL times.

Q
B. SAFETY PRECAUTIONS
WARNING: For your safety, the information in this manual must be followed to minimize the
risk of fire or explosion or to prevent property damage, personal injury, or loss of
life.
WARNING: The dryer must never be operated with any of the back guards, outer tops, or
service panels removed. PERSONAL INJURY or FIRE COULD RESULT.
1. DO NOT store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other
appliance.
2. Purchaser/user should consult the local gas supplier for proper instructions to be followed in the event the
user smells gas. The instructions should be posted in a prominent location.
3. WHAT TO DO IF YOU SMELL GAS...
a. DO NOT try to light any appliance.
b. DO NOT touch any electrical switch.
c. DO NOT use any phone in your building.
d. Clear the room, building, or area of ALL occupants.
e. Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions.
f. If you cannot reach your gas supplier, call the fire department.
4. Installation and service must be performed by a qualified installer, service agency, or gas supplier.
5. Dryer(s) must be exhausted to the outdoors.
6. Although ADC produces a very versatile machine, there are some articles that, due to fabric composition
or cleaning method, should not be dried in it.
WARNING: Dry only water washed fabrics. DO NOT dry articles spotted or washed in dry
cleaning solvents, a combustible detergent, or “ALL purpose” cleaner.
EXPLOSION COULD RESULT.
WARNING: DO NOT dry rags or articles coated or contaminated with gasoline, kerosene, oil,
paint, or wax.
EXPLOSION COULD RESULT.
WARNING: DO NOT dry mop heads. Contamination by wax or flammable solvents will create
a fire hazard.

R
WARNING: DO NOT use heat for drying articles that contain plastic, foam, sponge rubber, or
similarly textured rubberlike materials. Drying in a heated basket (tumbler) may
damage plastics or rubber and also may be a fire hazard.
7. A program should be established for the inspection and cleaning of lint in the heating unit area, exhaust
duct work, and inside the dryer. The frequency of inspection and cleaning can best be determined from
experience at each location.
WARNING: The collection of lint in the burner area and exhaust duct work can create a
potential fire hazard.
8. For personal safety, the dryer must be electrically grounded in accordance with local codes and/or the
National Electrical Code ANSI/NFPA NO. 70-LATEST EDITION, or in Canada, the Canadian Electrical
Codes Parts 1 & 2 CSA C22.1-1990 or LATEST EDITION.
NOTE: Failure to do so will VOID THE WARRANTY.
9. UNDER NO CIRCUMSTANCES should the dryer door switch, lint door switch, or heat safety circuit
ever be disabled.
WARNING: PERSONAL INJURY or FIRE COULD RESULT.
10. This dryer is not to be used in the presence of dry cleaning solvents or fumes.
11. Remove articles from the dryer as soon as the drying cycle has been completed.
WARNING: Articles left in the dryer after the drying and cooling cycles have been completed
can create a fire hazard.
12. READ and FOLLOW ALL CAUTION and DIRECTION LABELS ATTACHED TO THE DRYER.
WARNING: YOU MUST DISCONNECT and LOCKOUT THE ELECTRIC SUPPLY and
THE GAS SUPPLY BEFORE ANY COVERS or GUARDS ARE REMOVED
FROM THE MACHINE TO ALLOW ACCESS FOR CLEANING,
ADJUSTING, INSTALLATION, or TESTING OF ANY EQUIPMENT per
OSHA (Occupational Safety and Health Administration) STANDARDS.
13. For safety, proper operation, and optimum performance, the dryer must not be operated with a load less
than 66% (20 pounds [9.07 kg]) of its rated capacity.

S
M AXIMUM C APACITY ( DRY WEIGHT )60lbs.**27.2 kg
B
ASKET (T UMBLER ) D IAMETER 27-1/4" 69.22 cm
B
ASKET ( TUMBLER ) D EPTH 30" 76.2 cm
B
ASKET ( TUMBLER ) MOTOR 1/2 HP * 0.373 kw
Door Opening
(D IAMETER ) 21-1/2" * 54.61 cm
B
ASKET ( TUMBLER ) V OLUME 10.1 cu. ft. * 0.286 cu.m.
V
OLTAGE A VAILABLE
120-240v 1ø 60/50 Hz
208-240v 3ø 60/50 Hz
A
PPROX . W EIGHT (U NCRATED )850lbs.385.6 kg
A
PPROX . W EIGHT (C RATED )900lbs.408.2 kg
H
EAT I NPUT 144,000 btu/hr ** 36,288 kcal/hr
A
IRFLOW 800 cfm ** 22.65 cmm
I
NLET P IPE S IZE 3/4" N.P.T. --
E
XHAUST D UCT O UTLET 8" 20.32 cm
Gas
SECTION II
SPECIFICATIONS
A. SPECIFICATIONS
NOTE: ADC reserves the right to make changes in specifications at any time without notice or
obligation.
Shaded areas are stated in metric equivalents
* Per basket (tumbler).
** Total for both baskets (tumblers).

T
ADG-235D (Gas)
NOTE: ADC reserves the right to make changes in specifications at any time without notice or
obligation.

U
ADG-235ED (Gas)
NOTE: ADC reserves the right to make changes in specifications at any time without notice or
obligation.

V
SECTION III
INSTALLATION PROCEDURES
Installation should be performed by competent technicians in accordance with local and state codes. In the
absence of these codes, the installation must conform to applicable American National Standards: ANSI Z223.1-
LATEST EDITION (National Fuel Gas Code) or ANSI/NFPA NO. 70-LATEST EDITION (National Electrical
Code) or in Canada, the installation must conform to applicable Canadian Standards: CAN/CGA-B149.1-M91
(Natural Gas) or CAN/CGA-B149.2-M91 (L.P. Gas) or LATEST EDITION (for General Installation and Gas
Plumbing) or Canadian Electrical Codes Parts 1 & 2 CSA C22.1-1990 or LATEST EDITION (for Electrical
Connections).
A. UNPACKING/SETTING UP
Remove protective shipping material (i.e., plastic wrap and/or optional shipping box) from dryer.
NOTE: The access keys for the service doors are included in the information packet shipped in
the basket (tumbler). These keys should be removed and put in a safe place yet made
accessible because some will be needed throughout various phases in the installation of
the dryer.
Dryers are shipped with a coin box and coin box faceplate ONLY. The coin box lock is not included and
must be purchased elsewhere or the lock can be ordered as a parts order from the ADC factory.
The dryer can be moved to its final location while still attached to the skid or with the skid removed.
To unskid the dryer, locate and remove the four (4) bolts securing the base of the dryer to the wooden skid. Two
(2) are at the rear of the base and two (2) are located in the front. Once the bolts are removed, slide the dryer off
the skid.
With the skid removed, to make it easier to slide the dryer into its final position, slightly lower ALL four (4)
leveling legs, so that the dryer will slide on the legs instead of the base frame. The dryer is equipped with four
(4) leveling legs, one (1) at each corner of the dryer base. The hex head adjustment bolts for the two (2) front
leveling legs are located directly behind the lower access door, and the rear two (2) adjustments are directly
behind the lower rear back (guard) panel.
B. LOCATION OF THE DRYER
Before installing the dryer, be sure the location conforms to local codes and ordinances. In the absence of such
codes or ordinances the location must conform with the National Fuel Gas Code ANSI.Z223.1 LATEST
EDITION, or in Canada, the installation must conform to applicable Canadian Standards: CAN/CGA-B149.
1-M91 (Natural Gas) or CAN/CGA-B149.2-M91 (liquid propane [L.P.] Gas) or LATEST EDITION (for General
Installation and Gas Plumbing).
1. The dryer must be installed on a sound level floor capable of supporting its weight. Carpeting must be
removed from the floor area that the dryer is to rest on.
IMPORTANT: “The dryer must be installed on noncombustible floors only.”

NM
2. The dryer must not be installed or stored in an area where it will be exposed to water and/or weather.
3. The dryer is for use in noncombustible locations.
4. Provisions for adequate air supply must be provided as noted in this manual (refer to Fresh Air Supply in
Section D).
5. Clearance provisions must be made from noncombustible construction as noted in this manual (refer to
Dryer Enclosure Requirements in Section C).
Even though a 12-inch (30.48 cm) clearance is acceptable, it is recommended that the rear of the dryer be
positioned approximately 2 feet (0.61 meters) away from the nearest obstruction (i.e., wall) for ease of
installation, maintenance, and service. (Refer to the illustration below.)
6. provisions must be made for adequate clearances for servicing and for operation as noted in this manual
(refer to Dryer Enclosure Requirements in Section C).
7. Dryer must be exhausted to the outdoors in an area where correct exhaust venting can be achieved as
noted in this manual (refer to Exhaust Requirements in Section E).
8. Dryer must be located in an area where correct exhaust venting can be achieved as noted in this manual
(refer to Exhaust Requirements in Section E).
IMPORTANT: Dryer should be located where a minimum amount of exhaust duct will be
necessary.

NN
C. DRYER ENCLOSURE REQUIREMENTS
Bulkheads and partitions should be made of noncombustible materials and must be located a minimum of
12-inches (30.48 cm), 18-inches (45.72 cm) or more is recommended for ease of installation, maintenance, and
service) above the dryer’s outer top, except along the front of the dryer which may be closed in if desired.
NOTE: Even though a minimum of 12-inches (30.48 cm) above the dryer’s outer top is accept
able, a clearance of 18-inches (45.72 cm) or more is suggested for ease of installation
and service (electrical power connections).
NOTE: When fire sprinkler systems are located above the dryers, a minimum of 12-inches
(30.48 cm) above the dryer’s outer top is required.
NOTE: Allowances must be made for opening the control door.
Dryers may be positioned side wall to side wall. However, allowances must be made for opening and closing of
the control door and the lint door. It is suggested that the dryer be positioned about 2 feet (0.61 meters) away
from the nearest obstruction for ease of installation, maintenance, and service (to be measured from the back
guard). Refer to the illustration on the previous page (page 10) for details.
NOTE: Air considerations are important for proper and efficient operation.
D. FRESH AIR SUPPLY
Air supply (make-up air) must be given careful consideration to assure proper performance of each dryer. An
unrestricted source of 800 cfm (22.65 cmm) is necessary for each dryer. An unrestricted air entrance from the
outdoors (atmosphere) of a minimum of 1-1/2 square feet (0.14 square meters) is required for each dryer. This
area must be enlarged if louvers or registers cover the opening. It is not necessary to have a separate make-up
air opening for each dryer. Common make-up air openings are acceptable. However, they must be set up in
such a manner that the make-up air is distributed equally to the dryers. For example, for a bank of eight (8)
dryers, a total make-up air opening of 12 square feet (3.66 square meters) is required. Two (2) openings
measuring 2 feet by 3 feet (0.61 by 0.92 meters) - 6 square feet (0.56 square meters) - are acceptable. (Refer to
the illustration on page 12.)
Allowances must be made for remote or constricting passageways or where dryers are located at excessive
altitudes or predominantly low-pressure areas.
IMPORTANT: Make-up air must be provided from a source free of dry cleaning solvent fumes.
Make-up air that is contaminated by dry cleaning solvent fumes will result in
irreparable damage to the motors and other dryer components.

NO
IMPORTANT: Make-up air openings should not be located near duct work exhaust outlets.
If make-up air opening(s) are too close to the exhaust outlet, lint and fumes
may be drawn back into the dryer area through these openings.
NOTE: Component failure due to dry cleaning solvent fumes will VOID THE WARRANTY.

NP
E. EXHAUST REQUIREMENTS
Exhaust duct work should be designed and installed by a qualified professional. Improperly sized duct work
will create excessive back pressure which results in slow drying, increased use of energy, overheating of the
dryer, and shutdown of the burner by the airflow (sail) switches, burner hi-limits, or basket (tumbler) hi-heat
thermostats.
CAUTION: IMPROPERLYSIZED or INSTALLED EXHAUST DUCT WORK CAN
CREATE APOTENTIAL FIRE HAZARD.
The exhaust duct work should be laid out in such a way that the duct work travels as directly as possible to the
outdoors with as few turns as possible. When single dryer venting is used, the duct work from the dryer to the
outside exhaust outlet must not exceed 20 feet (6.1 meters). In the case of multiple (common) dryer venting, the
distance from the last dryer to the outside exhaust outlet must not exceed 20 feet (6.1 meters). The shape of the
exhaust duct work is not critical so long as the minimum cross-sectional area is provided.
1. Single Dryer Venting
Where possible, it is suggested to provide a separate exhaust duct for each dryer. The exhaust duct work
should be laid out in such a way that the duct work travels as directly as possible to the outdoors with as few
turns as possible. It is suggested that the use of 90º turns in ducting be avoided; use 30º or 45º angles
instead. The shape of the exhaust duct work is not critical so long as the minimum cross-sectional area is
provided.
IMPORTANT: Exhaust back pressure measured by a manometer at each basket (tumbler)
exhaust duct area must not exceed 0.3 inches of water column (7.4 mb).
It is suggested that the duct work from each dryer not exceed 20 feet (6.1 meters) with no more than two (2)
elbows. If the duct work exceeds 20 feet (6.1 meters) or has numerous elbows, the cross-sectional area of
the duct work must be increased in proportion to length or number of elbows in it.
IMPORTANT: For extended duct work runs, the cross-sectional area of the duct work can only
be increased to an extent. When the duct work approaches the maximum limits
as noted in this manual, a professional heating venting air conditioning (HVAC)
firm should be consulted for proper venting information.
The duct work should be smooth inside with no projections from sheet metal screws or other obstructions
which will collect lint. When adding ducts, the duct to be added should overlap the duct to which it is to be
connected. ALL duct work joints must be taped to prevent moisture and lint from escaping into the
building. Also, inspection doors should be installed at strategic points in the exhaust duct work for periodic
inspection and cleaning.

NQ
NOTE: When the exhaust duct work passes through a wall, ceiling, or roof made of combustible
materials, the opening must be 2-inches (5.08 cm) larger than the duct (ALL the way
around). The duct must be centered within this opening.
To protect the outside end of the horizontal duct work from the weather, a 90º elbow bent downward should
be installed where the exhaust exits the building. If the exhaust duct work travels vertically up through the
roof, it should be protected from the weather by using a 180º turn to point the opening downward. In either
case, allow at least twice the diameter of the duct between the duct opening and nearest obstruction.
IMPORTANT: DO NOT use screens or caps on the outside opening of the exhaust duct work.

NR
2. Multiple Dryer (common) Venting
If it is not feasible to provide separate exhaust ducts for each dryer, ducts from individual dryers may be
channeled into a “common main duct.” The individual ducts should enter the bottom or side of the main
duct at an angle not more than 45º in the direction of the airflow. The main duct should be tapered, with the
diameter increasing before each individual 8-inch (20.32 cm) duct is added.
IMPORTANT: No more than eight (8) dryers should be connected to one (1) main common
duct. (Refer to the illustration on page 16).
NOTE: Refer to the illustration on page 16 for examples of multiple dryer (common) venting.
The main duct may be any shape so long as the minimum cross-sectional area is provided. The illustration
on page 16 shows the minimum cross-sectional area for multiple dryer venting. These figures must be
increased in proportion if the main duct run from the last dryer to where it exhausts to the outdoors is
unusually long (over 20 feet [6.1 meters]) or has numerous elbows (more than two [2]) in it.
IMPORTANT: For extended duct work runs, the cross section area of the duct work can only
be increased to an extent. Maximum proportional duct work runs cannot
exceed 20 feet (6.1 meters) more than the original limitations of 20 feet (6.1
meters) with two (2) elbows. When the duct work approaches the maximum
limits as noted in this manual, a professional heating venting air conditioning
(HVAC) firm should be consulted for proper venting information
IMPORTANT: Exhaust back pressure measured by a manometer at each basket (tumbler)
exhaust duct area must not exceed 0.3 inches water column (W.C.) - 0.74 mb.
The duct work should be smooth inside with no projections from sheet metal screws or other obstructions
which will collect lint. When adding ducts, the duct to be added should overlap the duct to which it is to be
connected. ALL duct work joints must be taped to prevent moisture and lint from escaping into the
building. Also, inspection doors should be installed at strategic points in the exhaust duct work for periodic
inspection and cleaning.
NOTE: When the exhaust duct work passes through a wall, ceiling, or roof made of combustible
materials, the opening must be 2-inches (5.08 cm) larger than the duct (ALL the way
around). The duct must be centered within this opening.
To protect the outside end of the horizontal duct work from the weather, a 90º elbow bent downward
should be installed where the exhaust exits the building. If the exhaust duct work travels vertically up
through the roof, it should be protected from the weather by using a 180º turn to point the opening
downward. In either case, allow at least twice the diameter of the duct between the duct opening and
nearest obstruction.

NS
IMPORTANT: DO NOT use screens or caps on the outside opening of the exhaust duct work.